Both electricity and magnetism are some of the topics that have shaped up the dynamics of modern physics. We will have a look at some of the principles behind these two topics, their evolution history and how they relate to each other.
What Is Electricity
In the most basic of terms, we can define electricity as a bunch of particles that have been charged and are in continuous motion. To better understand what electricity is, we will have to have a good grasp of its basic operational principles.
Matter is basically made up of molecules which are basically many atoms. Each atom is known to contain protons (positive charges), electrons (negative charges) and neutrons (neutral charges) in their basic structure.
Basing our definition on this, we can have electricity in either static form or dynamic form. As the names suggest, static simply means the electrons at that point are immobile.
This means that the electrical charge has accumulated on in a specific place, with no flow of current.
What Is Magnetism
Comparing Electricity And Magnetism
Electricity and Magnetism can be classified as the two major facets of electromagnetism. We can break down the meaning of Electromagnetism as simply the electromagnetic force existing between particles that have been electrically charged.
This force is what binds the electrons inside a molecule to its nucleus therefore enhancing its structure.
History Of Electricity And Magnetism
Electricity and Magnetism were initially seen as two totally different and unique scenarios. After the 19th Century, it was discovered that they are inter-related and form what is uniquely called Electromagnetism.
We can trace the beginning of Electricity and Magnetism to the old Greek Antiquity years. This was when to get a better understanding of the theory for the two, you needed to apply ancient measures.
Various researchers have come out from the 18th century up until the 19th century to well define and shape our understanding of the same. Such researchers and scientists include the likes of Michael Faraday, August Coulomb and Benjamin Franklin.
Based on such ancient history, we have beginner pioneers like William Gilbert (1540-1603) who initiated the concept of magnetism. Famously referred to as “The Galileo of Magnetism”, he discovered and eventually published the fact that a magnet contains two poles.
Charles Francois Du Fay (1698-1739) also came up with a great discovery. He realized that rubbing any two objects together results in the production of some form of electric charge.
Then there is Benjamin Franklin (1706-1790) who came up with the lightning arrestor rod after he mistakenly shocking himself. This was based on his theory on a sharp iron needle on a metal sphere that tended to conduct away electricity from the sphere.
We also have Charles August Coulomb (1763-1806) who came up the Torsion Balance Theory. From this he developed Coulombs Law that states that any electrostatic force between two charged objects is proportional to the charge.
A Danish physicist by the name Hans Christian Oersted (1777-1851) responsible for discovering that magnetic fields can be generated from electricity. His theory proved that an electric current in a conductive wire is capable of deflecting a magnetized needle.
Another great scientist in the history of Electricity and Magnetism is Michael Faraday. He discovered magnetic induction in 1831 which is basically the production of an EMF from the interaction between an electric circuit and magnetic field.
Ancient Electromagnetism History
We can attribute the earliest discovery of magnetism to the Greeks who had clear knowledge of rubber amber and magnetite attractive forces. As early as 800BC, the Greeks were already mining magnetite in Thessaly, in the province of Magnesia.
The Greek accredited with being the first person to begin the study of magnetic forces was called Thales of Miletus. He discovered two things in his quest. First was that the magnetite had the ability to attract iron.
Secondly, he rubbed a fossil tree resin called amber and the result was that it attracted materials with a light weight. It is widely known that the word magnet came from the name of Magnesia province in Greece.
When it comes to ancient application, the very first known use was in the magnetic compass. Word has it that it was in China around the 26th Century BC but that is just a few historians’ opinion.
Other historians believe that either the Arabs or Italians invented it and shared the technology with China around 13th Century. Peter Peregrinus from France is the person credited with carrying out the first electromagnetic experiment.
He carried out experiments using lodestone and came up with the north and south ends of a magnet, calling them poles. He further found out that cutting any magnet into pieces will still give each piece it sown two poles.
Discovery Of Electromagnetism
For a concept that will eventually revolutionize the whole world, it is very strange that electromagnetism was accidentally discovered. Hans Christian Oersted was a Danish scientist demonstrating to some students in a lab.
He was trying to prove the point that there was no relation between electricity and magnetism. The demonstration involved placing a conductive wire next to a compass and passing some current through it.
The compass has a magnetic needle and the expectation was that there would be no movement of the needle. The needle, on passing the current on the wire maintained the direction towards the earth’s magnetic north.
once he was done proving that, one of the students took the wire and placed it in a different direction next to the compass. Contrary to what Oersted believed, the compass needle pointed towards the wire and no longer on the earths north.
To confirm this observation, he turned off the current on the wire to see the effect and the needle pointed back to the earths north. The discovery here by Oersted was that a magnetic field can be created from an electric current.
The strength of this magnetic field generated had enough intensity that drew the magnetic needle of the compass. This is how electromagnetism was discovered and its evolution has greatly impacted modern physics and inventions.
Electricity And Magnetism Timelines From Conception To Present
We can highlight some of the major developments of electricity and magnetism year by year. This means that we have to begin from their very discovery to the present technology.
Around 600BC, lodestones were discovered and their magnetic properties defined by Greek Philosophers. This around the same time that they discovered a mineral called Amber that had the ability to attract light materials once they are rubbed.
This same period saw the discovery of three ways of generating electricity namely by electromagnetic induction, static or by electrochemical. This was after Dr. William Gilbert researched on the magnet and amber reactions.
The working of a compass was later invented between 1100 BC and 1200 BC. It is around the same time that the floating compass and another having a pivot point were discovered.
More substances were found to be electric thanks to the discovery by William Gilbert (1544-1603) around the 16th Century. This is where vitreous and resinous electricity were discovered when amber was rubbed using different materials.
A German inventor and scientist called Otto von Guericke came up with a static electricity generator, the machine that produces static electricity. This actual time was around 1660 AD.
Thereafter, Stephen Gray came up with the conductors and non-conductors theory in 1729. He discovered that a charged body can passed electric power to another non-charged body when placed in contact.
This led to the discovery of the attraction and repulsion on electrical bodies. These two types of electricity were discovered by Gowen Knight in 1734.
After the discovery of natural magnets, Gowen Knight started the production of artificial magnets in 1740. This type of magnet for commercial use was very important especially to offshore navigators and natural scientific explorers.
Then came the electric capacitors invented by Pieter van Musschenbroek together with Ewald von Kleist from Netherlands and Pomerania respectively. This was in 1745 and the concept behind it was an electric charge could be temporarily stored.
From this charge conservation, an American called Benjamin Franklin in 1747 discovered that there were two types of stored charges. The electric forces existed as either repulsive or attractive forces symbolized by either the positive (+) or the negative (-) sign.
The first electric battery was later invented by Alessandro Volta who discovered that moisture between two electric plates can create electricity. He confirmed that you can transfer electricity from one point to another using a conductive wire.
The discovery of current came around 1820 and was by Andre Marie Ampere who came up with the laws touching on magnetic fields and their relation to current. This current is measured in Amps and is what conjoins magnetism and electricity basically because magnetism comes from it.
Michael Fraday (1791-1867) discovered Electromagnetic induction, a feat that was one of the best discoveries in the electromagnetic field in 1855. His reasoning behind all this was that magnetism could produce electricity the same way as magnetism could produce electricity.
Although they required heavy currents, arc lights were discovered in 1860 by Sir Humphrey Davey although large batteries were used. A brilliant incandescence was formed once two carbon rods are aligned together and maintained that way using current.
In as much as electric DC motors were still under experiments, Pacinotti in 1860 made one using an armature that was ring-wound. In 1871, Zenobe Theophile Gramme developed on Pacinotti’s concept and made a commercially viable motor.
As a replacement for the arc lights used for lighting up streets, constant potential lighting was discovered in 1871 and needed constant power supply. The DC Generator was thus invented giving rise to the birth of the power industry.
The genius responsible for inventing the alternating current system is a Serbian called Nikola Tesla in 1883. Since it was not possible to convey DC currents over long distances, Tesla experimented with rotating magnetic field from DC power generators.
George Washington capitalized Tesla’s invention and in 1886 started generating the first AC power. The power was only used for lighting since no AC motor was available for other output uses.
From then on, rapid developments were made like the Fission nuclear reactor by Otto Hahn in 1890 and the electronic amplifier in 1906 by Lee De Forest. Other discoveries around that time include cobalt steel magnets in 1917 by Honda and Takai and commercial steel magnets in 1919.
FM radios then came along courtesy of Edwin Armstrong in 1920 followed by magnets called Alnico having iron, nickel and aluminum invented by Mishima in 1930. This was hastily followed by transistors in 1950 by William Shockley then ceramic magnets in 1952 by the Phillips company.
Another great invention for modern electronics is the integrated circuit invented in 1953 by Jack Kilby. Rare earth magnets like Samarium-Cobalt were discovered in 1966 by Dr. Karl Strnat containing very high levels of energy.
Later, high energy electromagnetic products such as Neodymium Iron Boron came into existence. Such high energy compounds were developed by General Motors in 1983. From then on, advancements have been made on these existing technologies with modifications largely done.
Applications Of Electromagnetism
Through Electromagnetism, electricity and magnets find their way in our every day lives. Their applications is wide and varied across very many fields including:
- Power generators and transformers
- Healthcare Industry in MRI machines
- Control valves and industrial relays and electromechanical solenoids
- Electric bells and electronic buzzers
- Laboratory Mass Spectrometers
- Magnetic locks and magnetic separators
- Household appliances such as electric fans and cooling systems
- Sensors and actuators
- Magnetic levitation trains
In short, the benefits of electricity and magnetism we experience today have come a long way. It has been a series of innovations aiming to have better equipment that performance better with improved efficiency.